I used to have a set of vortec heads (the GMPP 330 crate engine) that I had pocket ported, vavle job, and spring upgrade. With the CC XE268, my old IROC would pull to 6K pretty easy. I know the yellow camaro with the ramjet and a weak cam ran well and they have the mini-ram drilled for the vortec bolt pattern.

I'm going to go ahead and start looking for another set of vortec heads for my L98 formula. I'm doing the tranny w/2700 stall speed vigilante right now, suspension late fall. I suspect that scoogin dickey will eventually get the tpi base out and I am kind of planning on going with that base and porting a set of slp runners/ cutting down the dividers an inch or two. I want to pull to 5500-5700, so I've been considering the ramjet but don't want to mess with the throttle body and fuel rail issues, so I'm curious on what your thoughts would be on the vortec heads w/slp ported runners. What cam would you guys recommend, I've thought about the LT4 hot cam w/1.6rr's, but want to make sure my intake will be able to take advantage of the cams range. I'm also going to look into the XE roller series. I figure 5700k would be OK for the LT4 hot cam, just have to make sure the heads are set up for .525".

I'm also consider Dart Iron Eagles and keeping the traditional intake pattern w/LTRs also, I am only interested in iron heads. Thanks for any comments . . .

I was gonna use a Superram, but that setup is similar to the one I was gonna use since I cant afford a Superram right now. The vortec's use an identical intake port to the LT1, so using a cam designed for an LT1 should be a good idea. The ZZ9 cam is similar to the LT4, but costs alot compared to the hot cam unless you can score a used one. Keep in mind the exhaust flow is radically different than the intake, a split set of rocker ratios or a cam with a more agressive exhaust profile would help evacuate exhaust gasses easier. I'm not sure on the max lift with a completely stock set of vortec heads, I know a spring change is a good idea, I don't think it's much. CC 268HR is a cam I hear alot about, but is kinda agressive and would work better with a Superram or miniram, although plenty or people have used it with high-flow LTR setups with success. Sounds like you want a powerband from around 2000-6000. I think you'll be OK with the ported SLP's. Don't hold your breath on the Vortec TPI base too long, it's past a year overdue. That's why I'm selling my vortec heads...tired of waiting. You can modify the vortec heads to accept an earlier intake, though.

well the release date is pretty set in september for the intake. scoggin has already paid everyone for the intake. The price is going to be kinda steep i think they said under 400 but it will be out. This means that not only the vortec and fast burns will be useable with tpi but also the edelbrock e-tec heads. I am a little upset my self that it took soo long but it is my fault for telling you guys about it. I have waited soo long i have lost interest in my car.

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90 IROC l98
last season best corected 13.62 @102
mods
full exhaust, AFPR, pulley, jet stage 1 chip, billet servo, 52mm throttle body, slp runners and some 1.6 RR's and a few other little things.
243 RWHP and 342 RWTQ with hot engine and 90 octain fuel

I originally had the vortec heads on a carbed car. I had another set I sold last winter when I got pissed about the base never coming out. I'm just trying to get my formula to 105mph w/ reasonable $$$ now so am considering them again. The vortec deal always looks good, but as always, the more I think it through, it gets cost prohibitive quickly. By the time I get the heads set up like I want, I'm at Iron Eagle price. Then throw in a base that will probably be close to a tpis bigmouth in $$ . . . ( I remember last year at this time waiting to buy the tpi base in September )

well they made a dyno run with the prototype base with the vortec heads and i beleve the zz-4 cam it made 375 hp. But they used mass air. The mass air sensor is very resrictive on a motor of that power level. i bet with a difrent cam that 400 hp could easily be possible. Too bad i have to save my money for the C-5.

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90 IROC l98
last season best corected 13.62 @102
mods
full exhaust, AFPR, pulley, jet stage 1 chip, billet servo, 52mm throttle body, slp runners and some 1.6 RR's and a few other little things.
243 RWHP and 342 RWTQ with hot engine and 90 octain fuel

375 seems kind of high with basically stock TPI (I'm assuming unported everything), stock vortec heads, and ZZ4 cam. I could see high torque, but I wouldn't think that it would produce that much more, if any, HP than the ZZ4 crate engine with HP numbers obtained via a carb. Heck, that is higher than the ramjet numbers (I know the ramjet cam is weak, but the ramjet is more of a "HP" revving intake than tpi) and is getting close to the stock fastburn crate engine with carb obtained numbers also. I'm not doubting, just debating.

well that is with the edelbrock runners and throttle body. but he only picked up like 3 hp with those. there is noting stock about the tpi manifold other than the plenum. apearantly the tpi manifold can support that kind of power with an aftermarket base. based on my RWHP #'s the stock manifold can make 300 hp with the stock engine when tuned properly. The base apears to be the most restrictive part of the system. The fast burn heads are not suited well to the zz-4 cam. they need more lift and duration to really shine. At low lift the vortec heads out flow the fast burns. I remimber a crate motor offerd by one GMPP store that made 385 hp with the same combo and a carb instead. I can't see the tpi with aftermarket componets taking more than 10 hp from an engine.

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90 IROC l98
last season best corected 13.62 @102
mods
full exhaust, AFPR, pulley, jet stage 1 chip, billet servo, 52mm throttle body, slp runners and some 1.6 RR's and a few other little things.
243 RWHP and 342 RWTQ with hot engine and 90 octain fuel